Different perspective: if I understand correctly, you've created a few different event buses. This strategy is a bit of a mid-point between a mail-box approach (where every actor has an individual queue) and a traditional event bus (where there is a single bus with all events.) The down side to the former is tighter coupling (as you will need to know where to send messages), while the latter has cognitive limitations w.r.t. event ordering and debugging.

I think that leaning towards the mailbox approach, as you've done (if I understand this,) is a good direction at this stage of the project.